The invention relates to a multi-chamber cartridge for multi-component plastic materials such as silicon, cement etc. . . with chambers arranged axially one behind the other for the reception of the two components.
Besides the well-known standard arrangements for two component cartridges with longitudinal separation of a cylindrical cartridge tube into two chambers by means of an intermediate separation wall or a co-axial inner tube (newer arrangement in the form of a co-axial cartridge), two-chamber cartridges with chambers arranged axially behind one another are also known. Examples here for can be found in U.S. Pat. Nos. 4,050,612, 4,029,236, and 4,961,520 as well as EP-0-624 403 a1
In the arrangement disclosed in EP-0 624 403 A1, the two chambers each include a piston for pressing the two components out of the cartridge. The components are disposed in a cylindrical cartridge tube axially one behind the other. The first chamber is formed between the cartridge tube and an inner tube which is arranged concentrically with the cartridge tube. This annular chamber is closed by an annular piston disposed in the back. The second chamber disposed axially behind the first chamber is formed by a piston which, forwardly, becomes wider in a beaker-like manner, and has a wall which abuts the inner wall of the cartridge tube. The beaker-like piston abuts with its front edge the annular piston of the first chamber so that, upon application of a pressure to the piston closing the rear chamber, the pressure is transmitted to the annular piston closing the front chamber and both pistons are advanced in unison. The rear chamber further includes a central lug which projects from the piston of the rear chamber forwardly and which enters the inner tube of the front chamber when the rear piston is moved forwardly. At its front end, the rear chamber is delimited by a radial wall which is disposed adjacent the end of the inner tube of the front chamber and which abuts with its outer end the inner beaker wall of the rear chamber.
The design of the known two-chamber cartridges requires the filling of the cartridge chambers after assembly of the cartridge from the discharge end which is relatively complicated and requires special equipment. In addition, the venting during filling is problematic.
It is the object of the present invention to provide a two-chamber cartridge with chambers arranged axially one after the other wherein each of the chambers can be filled easily with a standard filling apparatus.